vpFeatureMomentArea.cpp

/****************************************************************************
 *
 * This file is part of the ViSP software.
 * Copyright (C) 2005 - 2017 by Inria. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * ("GPL") version 2 as published by the Free Software Foundation.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See http://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 * Implementation of vpFeatureMomentArea associated to vpMomentArea
 *
 * Authors:
 * Manikandan Bakthavatchalam
 *
 *****************************************************************************/
#include <visp3/core/vpConfig.h>
#include <vector>
#include <limits>
#include <cassert>
#include <limits>   // numeric_limits

#include <visp3/visual_features/vpFeatureMomentArea.h>
#include <visp3/core/vpMomentObject.h>
#include <visp3/core/vpMomentGravityCenter.h>
#include <visp3/core/vpMomentArea.h>
#include <visp3/visual_features/vpFeatureMomentDatabase.h>

void vpFeatureMomentArea::compute_interaction(){

    interaction_matrices.resize(1);
    interaction_matrices[0].resize(1,6);

    // Retreive the moment object associated with this feature
    vpMomentObject mobj = moment->getObject();
    if (mobj.getType()==vpMomentObject::DISCRETE) {
        /*
         *  The interaction matrix for the discrete case is zero
         *  since the feature m00 is constant.
         *  Refer thesis of Omar Tahri 2005 [Section 3.4.22]
         */
        interaction_matrices[0][0][0] = 0.;
        interaction_matrices[0][0][1] = 0.;
        interaction_matrices[0][0][2] = 0.;
        interaction_matrices[0][0][3] = 0.;
        interaction_matrices[0][0][4] = 0.;
        interaction_matrices[0][0][5] = 0.;
    }
    else {
        // Get Xg and Yg
        bool found_xgyg;
        const vpMomentGravityCenter& momentGravity = static_cast<const vpMomentGravityCenter&>(moments.get("vpMomentGravityCenter",found_xgyg));
        if (!found_xgyg) throw vpException(vpException::notInitialized,"vpMomentGravityCenter not found");

        bool found_m00;
        const vpMomentArea& areamoment = static_cast<const vpMomentArea&>(moments.get("vpMomentArea", found_m00));
        if (!found_m00) throw vpException(vpException::notInitialized,"vpMomentArea not found");

        double Xg = momentGravity.getXg();
        double Yg = momentGravity.getYg();

        double a = areamoment.get()[0]; // Area scalar
        
        assert(std::fabs(a-mobj.get(0,0)) < a*std::numeric_limits<double>::epsilon());

        interaction_matrices[0][0][0] = -a*A;
        interaction_matrices[0][0][1] = -a*B;
        interaction_matrices[0][0][2] = (3*a)*(A*Xg+B*Yg)+(2*C*a);
        interaction_matrices[0][0][3] = 3*a*Yg;
        interaction_matrices[0][0][4] = -3*a*Xg;
        interaction_matrices[0][0][5] = 0.;
    }
}